Safety and effectiveness of intracardiac echocardiography in ventricular tachycardia ablation: a nationwide observational study.

Intracardiac echocardiography (ICE) utilized in conjunction with three-dimensional (3-D) mapping systems could enhance ventricular tachycardia (VT) ablation procedures. ICE has been increasingly used in VT ablation; however, the safety and effectiveness of VT ablation under the combined use of ICE remains unclear. The present study aimed to analyze the safety and short-term effects of VT ablation with or without ICE. We retrospectively enrolled patients who underwent initial VT ablation with a combination of ICE and a 3-D mapping system within 3 days of hospitalization and discharged from April 2011 to March 2017 using a nationwide Japanese inpatient database. Following enrollment, we conducted a propensity score-matching analysis to compare safety (in-hospital complications) and effectiveness (readmission within 30 days after discharge due to cardiovascular disease and readmissions within 30 days for repeat VT ablations) between patients who underwent VT ablation with (ICE group) and without ICE (non-ICE group). 3-D mapping systems were applied to both groups. We identified 5,804 eligible patients (1,272 and 4,532 patients in the ICE and non-ICE groups, respectively). One-to-one propensity score matching created a total of 1,147 pairs between the ICE and non-ICE groups. The ICE group showed a significantly lower prevalence of cardiac tamponade than the non-ICE group. There were no significant differences observed between the two groups regarding other outcomes concerning safety and effectiveness. Ventricular tachycardia ablation with ICE used in combination with a 3-D mapping system may reduce cardiac tamponade; however, no additional clinical advantages were noted in terms of safety and effectiveness.